Do I REALLY Need To Insulate A Van? The Truth About Van Insulation

Van Insulation Top 3

Here’s What You Need To Know About Van Insulation

Insulating a van is hard damn work. No two ways about it. There’s the planning, the gazillions of insulation options to choose from, all with weird names like Polyiso Board and strange terminology like R-Values and Thermal bridging.

There is no doubt that it’s pretty complicated. You can lose countless hours going down the rabbit hole until your head is spinning. 

Then, once you have figured out what to do, there is the time and money investment of actually installing insulation into your van. 

And even after all of this you will never really know just how good or bad of a job the insulation is doing. I mean, it’s not like you have 2 vans sitting there, one with insulation and one without so that you can easily see the differences.

Insulating a van is hard damn work. No two ways about it. And it takes time and money!

In My Situation, Do I Even Need Insulation?

When we started down our own van conversion journey in our Ford Transit Jumbo, It was the one big question on our mind – is insulating the van really worth it. 

The short answer… at least from our perspective gathered on our travels is a resounding…


I believe most people would be better served having insulation in their van as opposed to not having it. 

I’ll go into why I think insulating a van is worth it in a second, but first, there is a caveat –  I do feel that in nearly every situation, insulating your van will be the right option. But, of course there are certain circumstances where it may not be necessary.

When Don’t You Need Insulation In A Van?

There are situations where you don’t need to insulate a van. For instance, if you are just fixing up a cheap bomb of a van to use for a few weeks and sell once you are done, then you’re probably better off just buying yourself a good sleeping bag and saving a heap of time and money. 

Or, if you are just building a weekender van, and you know you are not doing any long term living in the van, then you may be willing to sacrifice a bit of comfort for the ease of getting on the road and onto your next adventure.

Van Insulation Test

Insulation really just slows down the inside of the van reverting to the temperature of the world outside. Without insulation, this process just happens a lot quicker. For instance, in our Ford Transit Jumbo conversion I timed how long it took in the van to heat up and cool down to outside temps.

It took about 3 hours to reach the outside temperature. This is having the van fully sealed up, in the shade (so that direct sun doesn’t skew the results).

Insulation really just slows down the inside of the van reverting to the temperature of the world outside. Without insulation, this process just happens a lot quicker.

When we travelled to cold climates we would go to bed warm and toasty, and in the morning 8 hours later, the van would be cool, sure, but no-where near as cold as outside. I know having three living bodies in the van exerts its own heat, but if we were in a non-insulated van the results would be considerably different.

The inside of the van would simply always be close to the same temperature as the outside of the van. The only way to mitigate this would be by additional heating or cooling methods, such as an air conditioner, which takes lots of energy.

With this in mind, if you know you are only travelling through temperate locations where the weather is typically pretty manageable, then you really won’t need insulation in the van. Maybe a 12 volt fan pointed at the bed will do the trick. 


4 reasons not to insulate your van

When Do You Need Van Insulation?

The reality is that if you are spending any serious amount of time living in a van, and want to be able to relax in your downtime without sweating or shivering then insulating your van to some extent is simply a must do. 

We travelled around Australia in our Ford Transit van, and enjoyed some absolutely unbelievable sights and sounds, but with the amazing locations came a fair bit of extreme weather. From blistering heat in South Australia, to antarctic winds in Tasmania, we had a wide gamut of different conditions. But through all of that, our insulation kept us comfortable.

Why You should Use Insulation

You’ve spent all of this money on your van, you’ve put in so much effort to prepare for your once in a lifetime road trip, you’ve designed and converted the van and hit the road. Everything is going so well. You get to your first campsite, cook dinner, turn in for the night… and then spend the next 10 hours freezing your ass off… all because you skipped the insulation process. 

The only objective of insulation is to provide you a pleasant living space. That’s it. So if that is something you want to experience on your road adventures, then insulation is a must!It really all comes down to two things. 

Temperature Control

A well insulate van will lessen the speed and severity of temperature changes inside the van. With the right ventilation (such as a MaxxFan Air, or strategically placed windows) it will keep the van cool during the warmer months, and with the right heating, can keep the van toasty warm in the cooler months. 

Noise Cancellation or Sound Deadening

An insulated van gives you not only temperature insulation, but also noise insulation! With the walls packed with insulation, especially insulation that presses on the metal walls of the van, the big metal sheeting of the van is less likely to vibrate. This will dramatically reduce outside noise. Also, sound waves will now have much more material to pass through before entering the van. 

What Is The Best Insulation To Use In A Van? Our Top 3 Picks


Van Insulation Top 3

After doing hours and hours of research for our van conversion, here are the top 3 products we think you should consider when insulating your van. All of these are brilliant, and you wouldn’t be putting a step wrong choosing any of them, or even combining them (as we did in our van build).

Sheep Wool for Van Insulation

Sheep wool insulation

Sheep wool is the gold standard in eco-friendly insulation. It is made for natural, 100% sustainable materials. It has superb breathability, and this fact alone can save you from needing vapor barriers in your van. 

Sheep wool is also sound absorbent. This means you can spend less money on the sound deadening in your van, as the sheep wool will contribute to that.

Sheep wool can be handled safely with your bare hands, and it’s easy enough to cut to size. 

The only downside really is the cost. It is one of the most expensive insulation types. 

Rigid Foam Board Van Insulation

Rigid Foam Board Insulation

Introducing the family of insulation materials called Rigid Foam Board insulation. This consists of – 

Extruded Polystyrene (XPS) Foam Boards

XPS and Polyiso have very high compression strength. This means you could stand on top of a sheet of XPS that is a half-inch thick and you wouldn’t damage it. It is slightly cheaper than Polyiso, but has a lower insulative power (only slightly lower).

Expanded polystyrene (EPS) Foam Boards.

This is your good old Styrofoam, or fairly close to it. It has a lower R-value, but is also a lot lighter on the wallet. A good choice for budget builds.

Polyisocyanurate (Polyiso) Foam Boards

The most expensive of the foam boards, and for good reason. It comes with the highest insulative power (R-value). It also comes with a foil outside on one or both sides. This foil provides a radiant heat barrier, which gives you additional insulative qualities. 

It is worth noting that PIR polyiso board has a performance dip in very cold climates. Once the temperature gets colder than 15c / 50f it’s insulative efficiency starts to deteriorate. By the time the temperature gets down to -20c / -4f it may be as much as 30 percent less efficient.

Also, spoiler alert! Polyiso is the insulation we used in our van conversion. 

Polyester Batt Insulation for Van Conversion

Polyester Batt Insulation

Polyester batts are a cheap alternative to the evils of fiberglass insulation. Polyester has the same insulative power, but can be installed safely without the need for protective equipment. 

Polyester is made out of Polytheylene Terephthalate (PET) fibre. Polyester batts are typically made from recycled materials (plastic bags and packaging). 

Polyester is safe to install and negates all of the negatives of some insulating products such as fiberglass (steer well clear). 

It negates all of the negatives of fiberglass, such as needing protective gear to install, and it also doesn’t come with any of the same health risks that fiberglass does. The fibers are non-irritant, non-allergenic and non-toxic.

We used Polyester batts in our van conversion too. It’s insulative power (R-value) plus its green credentials (made from recyclable materials) made us very keen to use it. 

What insulation to use where?

Here is what we think the best choice of materials for each install location is. After spending 12 months converting and travelling in the van full time, I’d like to think our choices worked out very well indeed. 


Best Floor Insulation In a Van Build Polyiso (560 × 260 px) (1)

Floor insulation

For the underfloor insulation in our van conversion, we used Polyiso Board.

Polyiso board is brilliant because it offers a remarkably high R-Value (a measurement of how effective the insulation is) per inch of space taken up. Considering you only have so much height in your van, you want to make sure that whatever insulation you use is sure to be efficient for the space used. 

For more information on insulating a van floor, including detailed instructions, see our van insulation mega guide!

Wall and Ceiling Insulation In a Van Build

Wall and Ceiling Insulation

We decided to use the polyiso board in both the ceiling and walls.

Again this was for the sheer efficiency of the product. In the larger wall cavities, the polyiso board was doubled up. This gave these parts of the wall a super insulative quality of R-13 (amazingly high!).

In all the hard to reach places in the walls, we used polyester batts.

The polyester batts could be cut apart and stuffed into corners and cavities, to fill the spaces the rigid Polyiso board couldn’t reach. After living in our van full time, I really do think we got the combination right. 

For a deeper dive into the world of van conversions and insulation please see our van insulation mega guide here

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